System and method of displaying a video stream

ABSTRACT

The present disclosure is generally directed to a video stream processing system and to a method of displaying a video stream. In a particular embodiment, the method includes receiving a video stream to be displayed on a display device. During a first time period, a low resolution version of the video stream is displayed while a full resolution version of the video stream is being recovered. The method further includes synchronizing the low resolution version of the video stream with the full resolution version of the video stream, and, during a second time period after the first time period, switching between display of the low resolution version of the video stream to display of the full resolution version of the video stream.

FIELD OF THE DISCLOSURE

The present disclosure relates to a system and method of displaying a video stream.

BACKGROUND

In a variety of situations in which television content is transmitted digitally, there can be a significant delay that occurs when switching from one source of video to another. Typically, the delay occurs while changing a television channel, but the delay also may occur when starting a new video stream in a number of situations. The delay depends on the specific situation, such as the type of video compression, the network bandwidth, and the decompression hardware. Further, the delay can occur when a new network stream is initiated and the delay can also occur when accessing video that is stored locally at Digital Video Recorder (DVR), a Personal Video Recorder (PVR), other local video storage device. Customers and users find this delay disconcerting. Moreover, the delay is of particular concern since analog televisions do not exhibit this type of delay.

Certain proposed solutions to the delay may be defined to fall into two classes. The simplest approach is to provide access to videos through a user interface that effectively hides the delay. This is the approach used by a variety of products in which the customer is effectively encouraged to navigate trough an Electronic Program Guide (EPG) and avoid directly switching channels. This method does not really solve the problem; it simply encourages the user to behave in a manner that causes the delay to be less noticeable. The second approach is to overpower the delay by bursting a very large amount of video data in a short amount of time. This technique requires the transmission of up to 10 times the normal amount of data in order to provide sufficient video data to begin rendering the video in a short amount of time after a channel is changed (e.g. less than 100 msec).

Both of these approaches attempt to address the problem of video delays, but the first requires customers' to change their behavior and the second places significant and expensive requirements on the local network and the rendering device.

Accordingly, there is a need for an improved system and method of displaying a video stream.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a block diagram of a video processing system;

FIG. 2 is a flow chart that illustrates a first embodiment of a method of displaying a video stream;

FIG. 3 is a flow chart that illustrates a second embodiment of a method of displaying a video stream; and

FIG. 4 is a flow chart that illustrates a third embodiment of a method of displaying a video stream.

DETAILED DESCRIPTION OF THE DRAWINGS

The present disclosure is generally directed to a video stream processing system and to a method of displaying a video stream. In a particular embodiment, the method includes receiving a video stream to be displayed on a display device. During a first time period, a low resolution version of the video stream is displayed while a full resolution version of the video stream is being recovered. The method further includes synchronizing the low resolution version of the video stream with the full resolution version of the video stream, and, during a second time period after the first time period, switching between display of the low resolution version of the video stream to display of the full resolution version of the video stream.

In a particular embodiment, the video stream processing system includes a user interface to detect a channel change request; a video detection module responsive to the user interface, and a video generation module responsive to the video detection module. The video detection module is to receive a video stream to be displayed on a display device. The video generation module is to communicate to the display device a first version of the video stream while the video detection module recovers a second version of the video stream. The first version of the video stream has a lower video display quality than the second version of the video stream. The video generation module includes synchronization logic to synchronize the first version of the video stream with the second version of the video stream, and the video generation module switches between communicating the first version of the video stream to communicate the second version of the video stream to the display device.

Referring to FIG. 1, a video stream processing system is illustrated and is designated 100. The video stream processing system 100 includes a video processing system 102 coupled via a communication link 120 to a video display device 130, such as a television. An example of an appropriate communication link is a coaxial cable. The video processing system 102 includes a video input 110 and includes a remote control interface 108. The remote control interface 108 receives signals, such as infrared signals 114, from a remote control device 112. The video processing system 102 further includes a video stream detection module 106 and a video generation module 104. The video stream detection module 106 receives the video input 110 and is responsive to signals received at the remote control interface 108.

The video stream detection module 106 forwards detected and processed video streams to the video generation module 104. The video generation module 104 provides a video signal to be communicated over the coaxial cable 120 for display at the video display device 130.

In a particular embodiment, the remote control device 112 provides a channel request signal to request a channel change. The channel request signal may be communicated using the infrared or other wireless communication signal 114 to the remote control interface 108. The remote control interface 108 then communicates the received channel change request to the video stream detection module 106. The video stream detection module 106, in turn, tunes to the requested channel within the video input 110. Further, the video stream detection module 106 provides instructions and processed signals to the video generation module 104. Then, the video generation module provides a video image signal that corresponds to the newly selected channel.

Referring to FIG. 2, a particular embodiment of a method of displaying a video stream is illustrated. The method includes detecting a channel change request, at 202. The method further includes receiving a video stream to be displayed on a display device, at 204. Further, the method includes displaying a low resolution version of the video stream on a display device during a first time period while recovering a full resolution version of the video stream, as shown at 206. Typically, the first time period is in the range of 1-3 seconds, based on the delay. As illustrated in FIG. 2, the method further includes the step of synchronizing the low resolution version of the video stream with the full resolution version of the video stream, as shown at 208. During a second time period, at 210, the method includes switching between the display of the low resolution version of the video stream to display of the full resolution version of the video stream. The second time period occurs after the first time period. Optionally, the method includes temporarily displaying a blurred image on the display device while switching between the low resolution version of the video stream to the full resolution version of the video stream, as shown at 212.

Referring to FIG. 3, another embodiment of a method of displaying a video stream is illustrated. The method includes detecting a channel change request, at 302, and receiving a video stream to be displayed on a display device, at 304. The method further includes, during a first time period, displaying a first version of the video stream on a display device while recovering a second version of the video stream, at 306. Typically, the first time period is in the range of 1-3 seconds based on the delay. In a particular exemplary embodiment, the video generation module 104 provides a low resolution version of the video stream of the newly selected channel while the video stream detection module 106 is processing the video stream to recover a full resolution version.

In a particular illustrative embodiment, an audio signal is provided to the display during the first time period and the audio signal is provided with full resolution such that a video display device user hears full audio while the first version of the video stream is being displayed. In a particular embodiment, the first version of the video stream has a lower video display quality than the second version of the video stream. For example, the first version of the video stream may have a reduced color set when compared to the second version of the video stream. As another example, the first version may have a reduced spectral frequency or other visual parameter that is degraded when compared to the second version of the video stream. Thus, the first version of the video stream consumes less bandwidth and may be displayed on the display device more quickly in response to the channel change request.

The method further includes synchronizing the first version of the video stream with the second version of the video stream, as shown at 308. During a second time period after the first time period, the method includes switching between the display of the first version of the video stream to the display of the second version of the video stream, as shown at 310. Optionally, during a third time period, the method includes displaying a third version of the video stream where the third version has a higher video display quality than the second version of the video stream. In a particular example, the first, second, and third versions of the video stream together comprise a portion of a progressive video stream. The progressive video stream initially presents a low quality image and then, presents added resolution and higher quality images over a sequence of successive time periods.

Referring to FIG. 4, another exemplary embodiment of a method of displaying a video stream is illustrated. The method includes detecting a channel change, at 402, and receiving a video stream to be displayed on the display device, at 404. During a first time period, a still image is displayed, as shown at 406. The still image is associated with the video stream. The still image is displayed while recovering the full motion video stream after the request for the channel change. During a second time period after the first time period, the method includes switching between display of the still image to display of the video stream as a full motion video, as shown at 408. In a particular illustrative embodiment, an audio signal is provided to the display during the first time period and the audio signal is provided with full resolution such that the video display device user hears full audio while the still image is being displayed. In another embodiment, the still image may comprise a title screen associated with the video stream or may include a frame derived from the video stream. The title screen may include information regarding the video stream such as the title of an episode, the title of a series, or the title of a movie that is to be displayed on the screen.

While particular illustrative methods of displaying a video stream have been described, it should be understood that many alternate methods may also be used with the system illustrated in FIG. 1. In a particular illustrative embodiment, the first period of time when a low resolution video stream is displayed may be less than three seconds. In another embodiment, a full resolution audio signal is provided to the display device during the first period of time while displaying the low resolution version of the video stream, such as when displaying a still image or a degraded or reduced bandwidth type video stream as illustrated. In a particular exemplary embodiment, the first time period in which a low resolution version of a video stream is displayed occurs within 100 milliseconds after detecting a channel change request, such as a channel change request initiated by a user of the remote control device 112 shown in FIG. 1. Thus, a user surfing through channels of a display device may quickly determine the particular content of individual channels.

Previous methods of handling channel change requests for digital video have produced significant delays. Ignoring such delays can negatively impact a customer perception of service quality. Since this is a significant and negative departure from previous customer experiences with analog television signals, such delays are undesirable. The methods described provide a user experience with reduced delay, and allows the user to quickly determine desirability of continuing to watch a particular channel. Thus, the disclosed method and system offers an improved video user experience.

The above disclosed subject matter is to be considered illustrative, and not restrictive, and the appended claims are intended to cover all such modifications, enhancements, and other embodiments which fall within the true spirit and scope of the present invention. Thus, to the maximum extent allowed by law, the scope of the present invention is to be determined by the broadest permissible interpretation of the following claims and their equivalents, and shall not be restricted or limited by the foregoing detailed description. 

1. A method of displaying a video stream, the method comprising: detecting a channel change; receiving a video stream corresponding to a changed channel, the received video stream to be displayed on a display device; during a first time period, displaying a first version of the received video stream while recovering a second version of the received video stream, the first version of the received video stream having a lower video display quality than the second version of the received video stream, wherein the first time period begins no more than approximately 100 milliseconds after the detected channel change; synchronizing the first version of the received video stream with the second version of the received video stream; and switching from display of the first version of the received video stream to display of the second version of the received video stream during a second time period.
 2. The method of claim 1, further comprising during a third time period, displaying a third version of the received video stream, the third version having higher video display quality than the second version, wherein the first version, the second version, and the third version together comprise a portion of a progressive video stream, wherein the progressive video stream initially presents a low quality image and then presents added resolution and higher quality images over a sequence of successive time periods.
 3. The method of claim 1, wherein the first version has a reduced color set with respect to the second version.
 4. The method of claim 1, further comprising displaying a blurred image on the display device while switching between the first version of the received video stream and the second version of the received video stream.
 5. The method of claim 1, wherein the first time period is less than approximately three seconds.
 6. A video stream processing system comprising: a user interface to detect a channel change request; a video detection module responsive to the user interface, the video detection module to receive a video stream to be displayed on a display device; and a video generation module responsive to the video detection module, the video generation module to communicate to the display device a first version of the received video stream while the video detection module recovers a second version of the received video stream, the first version of the received video stream having a lower video display quality than the second version of the received video stream, wherein the first version has a first resolution and the second version has a second resolution, wherein the second resolution is higher than the first resolution, the video generation module including synchronization logic to synchronize the first version of the received video stream with the second version of the received video stream; wherein the video generation module switches from communicating the first version of the received video stream to communicating the second version of the received video stream to the display device, and wherein the video generation module is to communicate to the display device the first version of the received video stream during a first time period, and wherein an audio signal with full resolution is provided to the display device during the first time period.
 7. The video stream processing system of claim 6, wherein the video generation modules switches from communicating the first version of the received video stream to communicating the second version of the received video stream to the display device during an interim time period, and wherein the display device displays a blurred image during the interim time period.
 8. The method of claim 6, wherein the first version has a reduced color set with respect to the second version.
 9. A method of displaying a video stream, the method comprising: receiving a video stream to be displayed on a display device; displaying a first portion of the video stream according to first display characteristics while recovering a second portion of the video stream, wherein the first display characteristics comprise a first resolution, and wherein the first portion of the video stream is displayed during a first time period and an audio signal is provided to the display device with full resolution during the first time period; switching from displaying the first portion of the video stream to displaying the second portion of the video stream, wherein the second portion of the video stream is displayed according to second display characteristics, wherein the second display characteristics comprise a second resolution, and the second resolution is higher than the first resolution; and displaying a blurred image on the display device while switching from displaying the first portion of the video stream to displaying the second portion of the video stream.
 10. The method of claim 9, wherein the first portion has a reduced color set with respect to the second portion. 